the potential use of theos satellite image for land use survey

The Potential Use of The Potential Use of THEOS Satellite Image THEOS Satellite Image

for for Land Use SurveyLand Use Survey

China-Thailand Geo-Informatics Workshop Series I: Agricultural Applications

June 29, 2010

Chamaporn PaiboonvorachatLand Use Analysis Division

Land Use Analysis Division

• Land Development Department

• Ministry of Agriculture and Cooperatives

Main responsibility

• Analyze remotely-sensed data for land use

survey and mapping

• Provide land use maps for agricultural land

use planning

Land Use Analysis Division• Hard copy land use maps: 1974

• Digital land use maps: 2000

• Revise maps every two years

2006 2008

2010

Land Use Analysis Division 1

• Mapping in East & Northeast of Thailand

• Overlay previous land use maps on satellite

image

• Visual interpretation - Digitizing

Aerial photo/Satellite Image

Land Use 2008

Objective of the study

•To utilize THEOS image in

monitoring the changing areas

•To assess the accuracy of the

classified areas comparing to ground

truth

Study area• Southwest of Nongyai District, Chonburi Province

Data Preparation

Pre-process

•SPOT 5 : resolution 2.5 meters

▫January 12, 2007

•THEOS : resolution 15 meters

▫October 10, 2009

Data Preparation•Geometric correction : Image-to-image registration

SPOT THEOS

Data Preparation•Rescale SPOT image

2.5 meters

15 meters

Data Preparation

•Atmospheric correction:

Empirical Line

Calibration

▫Forces the remotely-

sensed data to match in

situ spectral reflectance

measurements (Jensen,

2005)

Change Detection

• Differencing Vegetation

Index Images

• Normalized Difference

Vegetation Index

▫ ∆NDVIij = NDVIij(date2) – NDVIij(date1)

• Increase/decrease

vegetation cover

DecreasDecreaseded

Field Survey•Overlay previous land use map, marked

polygons, THEOS image

•Field check: GPS, compass, other instruments

Result

• High classification accuracy of 81.25%

Land use change

• Perennial crop: Eucalyptus, Oil palm, Cashew

nut Young para rubber plantation, cropland

Eucalyptus

SPOT THEOS

Para rubber

Pineapple

Land use change

• Croplands: Sugarcane, Cassava, Pineapple

Young para rubber plantation

SPOT THEOS

Para rubber

Pineapple

Eucalyptus Poultry farm

Uncertainty•Mainly found in croplands•Different time of taking images

SPOT THEOS

Pineapple Pineapple

Sugarcane Sugarcane

Conclusion

•More than 80% correct classification

•THEOS image is useful for change detection

•Provide more efficiency in survey in limited

time

20112011

•THEOS images should be offered in Central

and Southern Regions of Thailand

Thank youThank you